Angiotensin II when injected into brain induces sodium and water homeostatic states that are similar to those found in head injured patients. The enzymatic pathway for the generation of angiotensin II within brain tissue may be linked to a novel angiotensin- specific carboxypeptidase identified by the PI. This proposal will permit the isolation of angiotensin specific carboxypeptidase. Polyclonal antibodies will permit the subsequent cellular localization.